TEHRAN (Tasnim) - South African health officials said on Sunday that listeriosis has killed 180 people since the start of last year and originated at a food factory in the country's northeast.

Listeriosis is caused by a bacteria found in soil, water, vegetation and animal faeces, and can contaminate food, especially fresh meat, dairy, seafood. It is prevented by basic hygiene and washing food, AFP reported.

"The source of the present outbreak can be confirmed to be the Enterprise food production facility in Polokwane," said health minister Aaron Motsoaledi in a statement.

Products made at the plant would be subject to safety recalls, he added.

Enterprise could not immediately be reached for comment.

"We advise members of the public to avoid all processed meat products that are sold as ready-to-eat," said Motsoaledi.

The National Institute of Communicable Diseases (NICD) confirmed that 948 cases of listeriosis had been confirmed since Jan 1 2017, leading to 180 deaths.

The death toll stood at 172 as recently as Feb 22.

The United Nations has previously said South Africa's listeriosis outbreak is believed to be the largest-ever worldwide.

The disease mainly affects children and has a three-week incubation period, making it difficult to track.

Most of the current cases have been in Gauteng province, which includes the cities of Johannesburg and Pretoria, with other cases concentrated in Western Cape and KwaZulu-Natal provinces.

Contamination in humans can result in flu-like illness, infection of the bloodstream and, in severe cases, infection of the brain which can prove fatal.

People with compromised immune systems, like some of those living with AIDS and pregnant women, are at a heightened risk, according to the World Health Organization (WHO).

It advises people to wash hands and kitchen surfaces, keep raw and cooked food separate, to cook food thoroughly and store it in the fridge.